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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-06-10 05:30:17 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-06-10 05:30:17 -0300
commitd635711daa98be86d4c7fd01499c34f566b54ccb (patch)
treeaa5cc3760a27c3d57146498cb82fa549547de06c /arch/powerpc/lib/checksum_32.S
parentc91265cd0efb83778f015b4d4b1129bd2cfd075e (diff)
Linux-libre 4.6.2-gnu
Diffstat (limited to 'arch/powerpc/lib/checksum_32.S')
-rw-r--r--arch/powerpc/lib/checksum_32.S398
1 files changed, 243 insertions, 155 deletions
diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S
index 6d67e057f..d90870a66 100644
--- a/arch/powerpc/lib/checksum_32.S
+++ b/arch/powerpc/lib/checksum_32.S
@@ -14,68 +14,59 @@
#include <linux/sys.h>
#include <asm/processor.h>
+#include <asm/cache.h>
#include <asm/errno.h>
#include <asm/ppc_asm.h>
.text
/*
- * ip_fast_csum(buf, len) -- Optimized for IP header
- * len is in words and is always >= 5.
- */
-_GLOBAL(ip_fast_csum)
- lwz r0,0(r3)
- lwzu r5,4(r3)
- addic. r4,r4,-2
- addc r0,r0,r5
- mtctr r4
- blelr-
-1: lwzu r4,4(r3)
- adde r0,r0,r4
- bdnz 1b
- addze r0,r0 /* add in final carry */
- rlwinm r3,r0,16,0,31 /* fold two halves together */
- add r3,r0,r3
- not r3,r3
- srwi r3,r3,16
- blr
-
-/*
* computes the checksum of a memory block at buff, length len,
* and adds in "sum" (32-bit)
*
- * csum_partial(buff, len, sum)
+ * __csum_partial(buff, len, sum)
*/
-_GLOBAL(csum_partial)
- addic r0,r5,0
+_GLOBAL(__csum_partial)
subi r3,r3,4
- srwi. r6,r4,2
+ srawi. r6,r4,2 /* Divide len by 4 and also clear carry */
beq 3f /* if we're doing < 4 bytes */
- andi. r5,r3,2 /* Align buffer to longword boundary */
+ andi. r0,r3,2 /* Align buffer to longword boundary */
beq+ 1f
- lhz r5,4(r3) /* do 2 bytes to get aligned */
- addi r3,r3,2
+ lhz r0,4(r3) /* do 2 bytes to get aligned */
subi r4,r4,2
- addc r0,r0,r5
+ addi r3,r3,2
srwi. r6,r4,2 /* # words to do */
+ adde r5,r5,r0
beq 3f
-1: mtctr r6
-2: lwzu r5,4(r3) /* the bdnz has zero overhead, so it should */
- adde r0,r0,r5 /* be unnecessary to unroll this loop */
+1: andi. r6,r6,3 /* Prepare to handle words 4 by 4 */
+ beq 21f
+ mtctr r6
+2: lwzu r0,4(r3)
+ adde r5,r5,r0
bdnz 2b
- andi. r4,r4,3
-3: cmpwi 0,r4,2
- blt+ 4f
- lhz r5,4(r3)
+21: srwi. r6,r4,4 /* # blocks of 4 words to do */
+ beq 3f
+ mtctr r6
+22: lwz r0,4(r3)
+ lwz r6,8(r3)
+ lwz r7,12(r3)
+ lwzu r8,16(r3)
+ adde r5,r5,r0
+ adde r5,r5,r6
+ adde r5,r5,r7
+ adde r5,r5,r8
+ bdnz 22b
+3: andi. r0,r4,2
+ beq+ 4f
+ lhz r0,4(r3)
addi r3,r3,2
- subi r4,r4,2
- adde r0,r0,r5
-4: cmpwi 0,r4,1
- bne+ 5f
- lbz r5,4(r3)
- slwi r5,r5,8 /* Upper byte of word */
- adde r0,r0,r5
-5: addze r3,r0 /* add in final carry */
+ adde r5,r5,r0
+4: andi. r0,r4,1
+ beq+ 5f
+ lbz r0,4(r3)
+ slwi r0,r0,8 /* Upper byte of word */
+ adde r5,r5,r0
+5: addze r3,r5 /* add in final carry */
blr
/*
@@ -87,123 +78,220 @@ _GLOBAL(csum_partial)
*
* csum_partial_copy_generic(src, dst, len, sum, src_err, dst_err)
*/
+#define CSUM_COPY_16_BYTES_WITHEX(n) \
+8 ## n ## 0: \
+ lwz r7,4(r4); \
+8 ## n ## 1: \
+ lwz r8,8(r4); \
+8 ## n ## 2: \
+ lwz r9,12(r4); \
+8 ## n ## 3: \
+ lwzu r10,16(r4); \
+8 ## n ## 4: \
+ stw r7,4(r6); \
+ adde r12,r12,r7; \
+8 ## n ## 5: \
+ stw r8,8(r6); \
+ adde r12,r12,r8; \
+8 ## n ## 6: \
+ stw r9,12(r6); \
+ adde r12,r12,r9; \
+8 ## n ## 7: \
+ stwu r10,16(r6); \
+ adde r12,r12,r10
+
+#define CSUM_COPY_16_BYTES_EXCODE(n) \
+.section __ex_table,"a"; \
+ .align 2; \
+ .long 8 ## n ## 0b,src_error; \
+ .long 8 ## n ## 1b,src_error; \
+ .long 8 ## n ## 2b,src_error; \
+ .long 8 ## n ## 3b,src_error; \
+ .long 8 ## n ## 4b,dst_error; \
+ .long 8 ## n ## 5b,dst_error; \
+ .long 8 ## n ## 6b,dst_error; \
+ .long 8 ## n ## 7b,dst_error; \
+ .text
+
+ .text
+ .stabs "arch/powerpc/lib/",N_SO,0,0,0f
+ .stabs "checksum_32.S",N_SO,0,0,0f
+0:
+
+CACHELINE_BYTES = L1_CACHE_BYTES
+LG_CACHELINE_BYTES = L1_CACHE_SHIFT
+CACHELINE_MASK = (L1_CACHE_BYTES-1)
+
_GLOBAL(csum_partial_copy_generic)
- addic r0,r6,0
- subi r3,r3,4
- subi r4,r4,4
- srwi. r6,r5,2
- beq 3f /* if we're doing < 4 bytes */
- andi. r9,r4,2 /* Align dst to longword boundary */
- beq+ 1f
-81: lhz r6,4(r3) /* do 2 bytes to get aligned */
- addi r3,r3,2
- subi r5,r5,2
-91: sth r6,4(r4)
- addi r4,r4,2
- addc r0,r0,r6
- srwi. r6,r5,2 /* # words to do */
- beq 3f
-1: srwi. r6,r5,4 /* # groups of 4 words to do */
- beq 10f
- mtctr r6
-71: lwz r6,4(r3)
-72: lwz r9,8(r3)
-73: lwz r10,12(r3)
-74: lwzu r11,16(r3)
- adde r0,r0,r6
-75: stw r6,4(r4)
- adde r0,r0,r9
-76: stw r9,8(r4)
- adde r0,r0,r10
-77: stw r10,12(r4)
- adde r0,r0,r11
-78: stwu r11,16(r4)
- bdnz 71b
-10: rlwinm. r6,r5,30,30,31 /* # words left to do */
- beq 13f
- mtctr r6
-82: lwzu r9,4(r3)
-92: stwu r9,4(r4)
- adde r0,r0,r9
- bdnz 82b
-13: andi. r5,r5,3
-3: cmpwi 0,r5,2
- blt+ 4f
-83: lhz r6,4(r3)
- addi r3,r3,2
- subi r5,r5,2
-93: sth r6,4(r4)
+ stwu r1,-16(r1)
+ stw r7,12(r1)
+ stw r8,8(r1)
+
+ andi. r0,r4,1 /* is destination address even ? */
+ cmplwi cr7,r0,0
+ addic r12,r6,0
+ addi r6,r4,-4
+ neg r0,r4
+ addi r4,r3,-4
+ andi. r0,r0,CACHELINE_MASK /* # bytes to start of cache line */
+ beq 58f
+
+ cmplw 0,r5,r0 /* is this more than total to do? */
+ blt 63f /* if not much to do */
+ andi. r8,r0,3 /* get it word-aligned first */
+ mtctr r8
+ beq+ 61f
+ li r3,0
+70: lbz r9,4(r4) /* do some bytes */
+ addi r4,r4,1
+ slwi r3,r3,8
+ rlwimi r3,r9,0,24,31
+71: stb r9,4(r6)
+ addi r6,r6,1
+ bdnz 70b
+ adde r12,r12,r3
+61: subf r5,r0,r5
+ srwi. r0,r0,2
+ mtctr r0
+ beq 58f
+72: lwzu r9,4(r4) /* do some words */
+ adde r12,r12,r9
+73: stwu r9,4(r6)
+ bdnz 72b
+
+58: srwi. r0,r5,LG_CACHELINE_BYTES /* # complete cachelines */
+ clrlwi r5,r5,32-LG_CACHELINE_BYTES
+ li r11,4
+ beq 63f
+
+ /* Here we decide how far ahead to prefetch the source */
+ li r3,4
+ cmpwi r0,1
+ li r7,0
+ ble 114f
+ li r7,1
+#if MAX_COPY_PREFETCH > 1
+ /* Heuristically, for large transfers we prefetch
+ MAX_COPY_PREFETCH cachelines ahead. For small transfers
+ we prefetch 1 cacheline ahead. */
+ cmpwi r0,MAX_COPY_PREFETCH
+ ble 112f
+ li r7,MAX_COPY_PREFETCH
+112: mtctr r7
+111: dcbt r3,r4
+ addi r3,r3,CACHELINE_BYTES
+ bdnz 111b
+#else
+ dcbt r3,r4
+ addi r3,r3,CACHELINE_BYTES
+#endif /* MAX_COPY_PREFETCH > 1 */
+
+114: subf r8,r7,r0
+ mr r0,r7
+ mtctr r8
+
+53: dcbt r3,r4
+54: dcbz r11,r6
+/* the main body of the cacheline loop */
+ CSUM_COPY_16_BYTES_WITHEX(0)
+#if L1_CACHE_BYTES >= 32
+ CSUM_COPY_16_BYTES_WITHEX(1)
+#if L1_CACHE_BYTES >= 64
+ CSUM_COPY_16_BYTES_WITHEX(2)
+ CSUM_COPY_16_BYTES_WITHEX(3)
+#if L1_CACHE_BYTES >= 128
+ CSUM_COPY_16_BYTES_WITHEX(4)
+ CSUM_COPY_16_BYTES_WITHEX(5)
+ CSUM_COPY_16_BYTES_WITHEX(6)
+ CSUM_COPY_16_BYTES_WITHEX(7)
+#endif
+#endif
+#endif
+ bdnz 53b
+ cmpwi r0,0
+ li r3,4
+ li r7,0
+ bne 114b
+
+63: srwi. r0,r5,2
+ mtctr r0
+ beq 64f
+30: lwzu r0,4(r4)
+ adde r12,r12,r0
+31: stwu r0,4(r6)
+ bdnz 30b
+
+64: andi. r0,r5,2
+ beq+ 65f
+40: lhz r0,4(r4)
addi r4,r4,2
- adde r0,r0,r6
-4: cmpwi 0,r5,1
- bne+ 5f
-84: lbz r6,4(r3)
-94: stb r6,4(r4)
- slwi r6,r6,8 /* Upper byte of word */
- adde r0,r0,r6
-5: addze r3,r0 /* add in final carry */
+41: sth r0,4(r6)
+ adde r12,r12,r0
+ addi r6,r6,2
+65: andi. r0,r5,1
+ beq+ 66f
+50: lbz r0,4(r4)
+51: stb r0,4(r6)
+ slwi r0,r0,8
+ adde r12,r12,r0
+66: addze r3,r12
+ addi r1,r1,16
+ beqlr+ cr7
+ rlwinm r3,r3,8,0,31 /* swap bytes for odd destination */
blr
-/* These shouldn't go in the fixup section, since that would
- cause the ex_table addresses to get out of order. */
-
-src_error_4:
- mfctr r6 /* update # bytes remaining from ctr */
- rlwimi r5,r6,4,0,27
- b 79f
-src_error_1:
- li r6,0
- subi r5,r5,2
-95: sth r6,4(r4)
- addi r4,r4,2
-79: srwi. r6,r5,2
- beq 3f
- mtctr r6
-src_error_2:
- li r6,0
-96: stwu r6,4(r4)
- bdnz 96b
-3: andi. r5,r5,3
- beq src_error
-src_error_3:
- li r6,0
- mtctr r5
- addi r4,r4,3
-97: stbu r6,1(r4)
- bdnz 97b
+/* read fault */
src_error:
- cmpwi 0,r7,0
- beq 1f
- li r6,-EFAULT
- stw r6,0(r7)
-1: addze r3,r0
+ lwz r7,12(r1)
+ addi r1,r1,16
+ cmpwi cr0,r7,0
+ beqlr
+ li r0,-EFAULT
+ stw r0,0(r7)
blr
-
+/* write fault */
dst_error:
- cmpwi 0,r8,0
- beq 1f
- li r6,-EFAULT
- stw r6,0(r8)
-1: addze r3,r0
+ lwz r8,8(r1)
+ addi r1,r1,16
+ cmpwi cr0,r8,0
+ beqlr
+ li r0,-EFAULT
+ stw r0,0(r8)
blr
-.section __ex_table,"a"
- .long 81b,src_error_1
- .long 91b,dst_error
- .long 71b,src_error_4
- .long 72b,src_error_4
- .long 73b,src_error_4
- .long 74b,src_error_4
- .long 75b,dst_error
- .long 76b,dst_error
- .long 77b,dst_error
- .long 78b,dst_error
- .long 82b,src_error_2
- .long 92b,dst_error
- .long 83b,src_error_3
- .long 93b,dst_error
- .long 84b,src_error_3
- .long 94b,dst_error
- .long 95b,dst_error
- .long 96b,dst_error
- .long 97b,dst_error
+ .section __ex_table,"a"
+ .align 2
+ .long 70b,src_error
+ .long 71b,dst_error
+ .long 72b,src_error
+ .long 73b,dst_error
+ .long 54b,dst_error
+ .text
+
+/*
+ * this stuff handles faults in the cacheline loop and branches to either
+ * src_error (if in read part) or dst_error (if in write part)
+ */
+ CSUM_COPY_16_BYTES_EXCODE(0)
+#if L1_CACHE_BYTES >= 32
+ CSUM_COPY_16_BYTES_EXCODE(1)
+#if L1_CACHE_BYTES >= 64
+ CSUM_COPY_16_BYTES_EXCODE(2)
+ CSUM_COPY_16_BYTES_EXCODE(3)
+#if L1_CACHE_BYTES >= 128
+ CSUM_COPY_16_BYTES_EXCODE(4)
+ CSUM_COPY_16_BYTES_EXCODE(5)
+ CSUM_COPY_16_BYTES_EXCODE(6)
+ CSUM_COPY_16_BYTES_EXCODE(7)
+#endif
+#endif
+#endif
+
+ .section __ex_table,"a"
+ .align 2
+ .long 30b,src_error
+ .long 31b,dst_error
+ .long 40b,src_error
+ .long 41b,dst_error
+ .long 50b,src_error
+ .long 51b,dst_error